Electron discharge device and support therefor



March 17, 1936. B. SALZBERG ELECTRON DISCHARGE DEVICE AND SUPPORT THEREFOR Filed Sept. 12, 1954 .llllllllllll w R Y E 5 4R v 0 mm n Patented Mar. 17, 1936 UNITED STATES PATENT OFFICE SUPPORT Bernard Salzberg, East THEREFOR Orange, N. J assignor to Radio Corporation of America, a corporation of Delaware Application September 12, 1934, Serial No. 743,651

8 Claims.

My invention relates to electron discharge devices for use at very high frequencies, and more particularly to mountings and supports for such devices.

Electron discharge devices are usually mounted or supported in the conventional type of socket having contacts which cooperate with the terminals of the electron discharge device mounted in the socket. The circuit elements, such as bypass condensers and the like are separate units connected by the ordinary wiring connections to the terminals of the discharge device thru the socket. These wiring connections introduce into the circuit capacitance, inductance and resistance which is of considerable effect at very high frequencies or ultra-short waves. At very high fresuencies the dielectric losses thru the insulation of the socket between the terminals connected to the radio frequency electrodes or between terminals connected to the radio frequency electrodes and the radio frequency grounded electrodes of the electron discharge device may become serious. Large capacitances between the electrode leads and large inductances and resistances due to the additional lead length necessary when using conventional sockets are also introduced into the circuit. These relatively large dielectric losses, capacitances, inductances and resistances introduce factors which may adversely affect the operation of a tube at ultrahigh frequencies.

An object of my invention is to provide a mounting or support for electron discharge devices for use at high frequencies in which dielectric losses, capacitances, inductances and resistances present when the conventional socket is used, are materially reduced so that the support is particularly suitable for ultra-high frequency devices.

Another object of my invention is to provide a composite tube socket and condenser in which the condenser electrodes themselves support the discharge device.

A further object of my invention is to provide a tube socket and condenser arrangement which also carries the associated circuit elements used at ultra-high frequencies.

e novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims, but the invention itself will best be understood by reference to the following description taken in connection with the accompanying drawing in which Figure 1 shows a support made in accordance with my invention and a tube for use at high frequencies with its associated elements mounted on the support; Figure 2 is a vertical section taken along the line 22 of Figure 1 and showing a detail of construction; Figure 3 is a plan view of a modification of a support made 5 in accordance with my invention; Figure 4 is an enlarged perspective view showing a detail of construction of the support shown in Figure 3; and Figure 5 is a vertical section taken along the line 5-5 of Figure 3. 10

The electron discharge device of tube ID, for which my support is particularly useful, is of the type described and claimed in my co-pending application, Serial No. 732,028, filed June 23, 1934 and assigned to the same assignee as the present application. It has an indirectly heated cathode and radial tube terminals, including heater terminals l I, a cathode terminal 12, anode terminal 13 and grid terminal l4. Between the anode terminal l3 and the grid terminal 14 is connected a coil [5 and condenser l6 forming with the tube Ill an oscillator circuit. A grid leak I1 is connected at one end to the grid lead and at the other by a screw M3 to the metal base plate IQ of the tube support.

As shown in Figure 1, a support made in accordance with my invention for supporting the tube I0 and its associated elements comprises the metallic base plate [9 which may be provided with an elongated aperture or opening 20 into which the electron discharge device and associated circuit elements may extend. This base plate is preferably grounded, and has positioned on it the thin insulating sheets 2i and 22, preferably of mica. For supplying current to the cathode heater there are mounted on the mica sheet 2| metallic plates 23 and 24 provided at one end with U-shaped spring clip type contacts 25 and 26 for receiving and holding the radial heater terminals H and at the other end with binding posts 21 and 28 which may hold the plates 23 and 24 in place and to which the heater voltage supply may be applied. These plates 23 and 24 form, with the base plate IS, a pair of by-passing condensers for the heater terminals.

The method of supporting the binding posts 21 and 28 on and insulating them from the base plate I 9 is shown in more detail in Figure 2. The back of the base plate is provided with an insulating sheet 28, preferably of mica. The bindr ing post is provided with a screw 30 and is secured to the back plate I!) out of contact and insulated therefrom by means of the nut 3|. In this way the binding posts support the plates 23 and 24 on the mica to form a pair of by-passing condensers and at the same time furnish the heater supp-1y voltages to the tube Ii] without grounding the binding posts.

Insulating sheet 2! is provided with an aperture 32 in which is a cathode connector comprising plate 33 positioned in contact with the base plate '19 and secured to the base plate by the screw 34,

the plate 33 being provided with a U-type spring clip 35 for receiving the cathode terminal I2 of the tube In.

Positioned on the insulating sheet 22 for supplying voltage to the anode of tube H] is a metal plate 31 forming with the back plate IS a bypassing condenser. Plate 31 has positioned thereon a binding post 38 mounted in the same manner as shown in Figure 2 to which the anode potential is applied thru the conductor 39 connected to the coil I5.

It will thus be seen that I have not only provided a novel support for the tube l0 comprising both a socket and condenser by-passing arrangement, but have also provided means for supporting the tube and all the associated circuit elements upon the base plate l9 substantially reducing the connecting wires necessary. This arrangement-substantially reduces all capacitance as well as the inductance between the electrode leads and tube terminals thereby permitting operation at very high frequencies since elimination at these capacitances and inductances reduce the inherent capacity and inductance of the circuit. Dielectric between leads has been practically eliminated so that the dielectric loss is materially reduced.

In the modification shown in Figure 3, the base plate 4!], which may also be used to provide an interstage shield in a multi-stage transmitter or receiver may be provided with an opening or aperture 4| thru which the tube I0 extends. Concentric with the opening is a sheet insulator 42, preferably of mica, and in the form of a ring. For providing tube terminal contacts there are mounted on this sheet insulator the metallic plates 43 which with the base plate 40 form by-passing condensers for the tube terminals. These plates are provided with spring contacts 44 which engage the terminals of the tube. The plate connected to cathode terminal [2 may be connected to the base plate 40. Sections of the mica ring between the spring contacts may be cut out as shown at G5 to reduce the dielectric leakage between the electrode terminals. The plates 43 as shown most clearly in Figure 5 are secured to the sheet insulator or insulating member 42 and back plate 40 in a manner similar to that shown in Figure 2. Concentric with and positioned on the back plate A!) .is a collar like member 16, preferably of insulating material and having an outwardly extending flange 41 fastened to the base plate 4%; for example, by means of rivets 48 and an inwardly extending flange 39 having slots 50 thru which the tube terminals are inserted when the tube-is-placed in position on the support. Mounted beneath the flange 39 and secured thereto by rivets 5! is an insulating ring 52 of resilient insulating material preferably mica and provided with slots 53. When the tube is'inserted into the support the terminals ll bend the portions of the insulating material on opposite sides of the slot downwardly to permit passage of terminal, these portions returning to their initial position to close slot 50 after the tube has been inserted in position in the support, the tube being turned thru a small angle to engage the terminals of the tube under the spring contacts 44.

While I have indicated the preferred embodiments of my invention of which I am now aware and have also indicated only one specific application for which my invention may be employed, it will be apparent that my invention is by no means limitedto the exact forms illustrated or the use indicated, but that many variations may be made in the particular structure used and the purpose for which it is employed without departing from the scope of my invention as set forth in the appended claims.

What I claim as new is- 1. A'support for an electron discharge device having an envelope provided with radially directed terminals extending from and positioned around said envelope, said support comprising a metal base plate, metal plates mounted on and parallel to said base plate on one side of said base plate and insulated from one another, each of said metal plates having a contact clip to engage and hold a terminal of said electron dis-. charge device and thin sheet insulation interposed .between each of said metal plates and said base plate whereby each of said metal plates and said base plate constitute an electrical condenser connected directly to a terminal of said electron discharge device.

2. A support for an electron discharge device having radially directed terminals, said support comprising a metal base plate, sheet insulation mounted on said base plate, metal plates positioned on the opposite side of said sheet insulation from said base plate and insulated. from each other, each of said metal plates being provided with contact clip for engaging and holding a terminal of said electron discharge device and means for maintaining said metal plates, said base plate and said sheet insulation in position whereby each of said metal plates and said base plate constitute an electrical condenser connected directly to a terminal of the electron discharge device.

3. A support for an electron discharge device having an envelope provided with radially directed terminals extending from and positioned around said envelope, including a metal base plate having an aperture therein, thin sheet insulation mounted on said base plate adjacent said aperture, metal plates mounted on the opposite side of said sheet insulation from said base plate with portions adjacent said aperture and contacts provided on said portions of said plates for receiving and holding the terminals of the electron discharge device.

4. A support for an electron discharge device having radially directed terminals, including a metal base plate having an aperture into which the electron discharge device is extended, sheet insulation mounted on said base plate adjacent said aperture, metal plates mounted on said sheet insulation for forming with said base plate by-passing condensers and having portions positioned adjacent said aperture, and a spring contact provided on each of said portions adjacent said aperture for receiving and holding a terminal of the electron discharge device. 5

5. A support for an electron discharge device having radially directed terminals, including a metal base plate having an aperture into which the electron discharge device is extended, sheet insulation mounted on said base plate adjacent said aperture, metal plates mounted on said sheet insulation for forming with said base plate bypassing condensers and having portions positioned adjacent said aperture, a spring contact provided on each of said portions adjacent said aperture for receiving and holding a terminal of said electron discharge device, and binding posts securing said metal plates to said base plate and insulated from said base plate.

6. A support for an electron discharge device having radially directed terminals, said support including a metal base plate having an aperture therein, a ring shaped member of sheet insulation mounted on said plate concentric with said aperture, metal plates mounted on said ring shaped member to provide with said base plate by-passing condensers, contact clips on said metal plates adjacent said aperture for receiving and holding the terminals of said electron discharge device.

7. A support for an electron discharge device having radially directed terminals, including a metal base plate, a ring shaped member of sheet insulation mounted on said plate, metal plates mounted on said ring shaped member to provide with said base plate by-passin'g condensers, contact clips on the metal plates on said ring shaped member for receiving and holding the terminals of said electron discharge device, and a collar concentric with said ring shaped member and secured to said base plate and having an inwardly extending flange provided with radial slots thru which the terminals of said electron discharge device are inserted when the electron discharge device is mounted in the support.

8. A support for an electron discharge device having radially directed terminals, including a metal base plate having an aperture therein, a ring shaped member of sheet insulation mounted on said plate concentric with said aperture, metal plates mounted on said ring shaped memher to provide with said base plate by-passing condensers, spring contacts on the metal plates on said ring shaped member adjacent said aperture for receiving the terminals of said electron discharge device and a collar secured to said base plate and concentric with said aperture and insulating ring and having an inwardly extending flange provided with radial slots thru which the terminals on said tube are inserted when the electron discharge device is mounted in the support, and means on said flange for yieldingly closing the slots.

BERNARD SALZBERG. 

